/Engine/Source/Editor/UnrealEd/Public/EditorModeManager.h
Returns true if the current mode is not the specified ModeID. Also optionally warns the user.
true if the current mode is not the specified mode.
bool EnsureNotInMode ( FEditorModeID ModeID, const [FText](API\Runtime\Core\Internationalization\FText) & ErrorMsg, bool bNotifyUser ) const